6561500403 has 8 divisors (see below), whose sum is σ = 8757240016. Its totient is φ = 4370047200.

The previous prime is 6561500401. The next prime is 6561500411. The reversal of 6561500403 is 3040051656.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6561500403 - 2¹ = 6561500401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6561500401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1068028 + ... + 1074153.

It is an arithmetic number, because the mean of its divisors is an integer number (1094655002).

Almost surely, 2^6561500403 is an apocalyptic number.

6561500403 is a deficient number, since it is larger than the sum of its proper divisors (2195739613).

6561500403 is a wasteful number, since it uses less digits than its factorization.

6561500403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2143205.

The product of its (nonzero) digits is 10800, while the sum is 30.

The square root of 6561500403 is about 81003.0888485124. The cubic root of 6561500403 is about 1872.1230335096.

The spelling of 6561500403 in words is "six billion, five hundred sixty-one million, five hundred thousand, four hundred three".